We've been filing as many as 3-5 states each year for the last 10 years of fulltiming. But only one state is our residence and the rest are filed as non-residents. Very few issues, except with Kansas in 2013. To get a $7 refund, they wanted ALL State and Federal Tax returns and W2s. Ignored it since it would have cost more than $7 to get all the paperwork together. Missed the letter that they would disallow our KS Withholding and we would owe them as FL UPS Store didn't forward our mail on time.
Finally got it straightened out this year. But had to pay $50 (because it went past due date) for them to review it and will be getting an $8+ check in the mail next week.
Forgot to mention: projects last anywhere from 3-8 mos. But they usually roll over into a 2nd year, so have to file two years in a row in some states.
